package com.ruoyi.supermarket.annotation;

import com.ruoyi.common.utils.SecurityUtils;
import com.ruoyi.supermarket.annotation.AutoFill;
import com.ruoyi.supermarket.annotation.OperationType;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

import java.lang.reflect.Method;
import java.time.LocalDateTime;

/**
 * 自定义切面，实现公共字段填充处理逻辑
 */
@Aspect
@Component
public class AutoFillAspect {

    /**
     * 切入点
     */
    @Pointcut("execution(* com.ruoyi.supermarket.mapper.*.*(..)) && @annotation(com.ruoyi.supermarket.annotation.AutoFill)")  //切点表达式
    public void autoFillPointCut(){
    }

    /**
     * 前置通知，在通知中进行公共字段的赋值
     */
    @Before("autoFillPointCut()")   
    public void autoFill(JoinPoint joinPoint){
        //获取到当前被拦截的方法上的数据库操作类型
        MethodSignature signature = (MethodSignature) joinPoint.getSignature(); //方法签名对象
        AutoFill autoFill = signature.getMethod().getAnnotation(AutoFill.class); //获得方法上的注解对象
        OperationType operationType = autoFill.value(); //获得数据库操作类型

        //获取到当前被拦截的方法的参数--实体对象
        Object[] args = joinPoint.getArgs();
        if(args == null || args.length == 0){
            return;
        }
        Object entity = args[0];
        //准备赋值的数据
        LocalDateTime now = LocalDateTime.now();
        String username = SecurityUtils.getLoginUser().getUsername();
        //根据当前不同的操作类型，为对应的属性通过反射来赋值
        if(operationType == OperationType.INSERT){
            //为4个公共字段赋值
            try {
                Method setCreateTime = entity.getClass().getDeclaredMethod("setCreateTime", LocalDateTime.class);
                Method setCreateUser = entity.getClass().getDeclaredMethod("setCreateName", String.class);
                //通过反射为对象属性赋值
                setCreateTime.invoke(entity,now);
                setCreateUser.invoke(entity,username);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }else if(operationType == operationType.UPDATE){
            //为2个公共字段赋值
            try {
                Method setUpdateTime = entity.getClass().getDeclaredMethod("setUpdateTime", LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod("setUpdateName", String.class);

                //通过反射为对象属性赋值
                setUpdateTime.invoke(entity,now);
                setUpdateUser.invoke(entity,username);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }

    }
}
